Reinforced die-block.



W. R. FORSYTH.

REINFORCED DIE BLOCK.

APPLICATION FILED AUG-3,1916.

.11. $89 ,736., Patented J une 12, 1917.

jet/@7350? mm; 23. 1 0 719 5% c ays REINFORCED DIE-BLOCK.

App1ieation filed August 3, 1916.

To all whom it may concern:

Be it known that 1, WILLIAM R. FoRsYTri, a citizen of the United States, residing at Swampscott, in the county of Essex and State of Massachusetts, have invented new and useful Improvements in Reinforced Die-Blocks, of which the following is a specification.

This invention relates to wooden die blocks used in die presses for cutting out blanks from sheet material such as leather. Such blocks are usually built up in sections, and each section is built up in pieces, thus to utilize small pieces of wood for the sake of economy. The pieces are rectangular and are glued together to form the sections separately, and the sections are arranged in a series and glued together to make a block which is, to all intents and purposes, a unit when completed. The joints and the grain of all the pieces extend from top to bottom.

The style of block to which the present invention relates is that above described. For the purpose of keeping the pieces and sections from being separated by the stresses encountered in a die press, I apply clamping bars to the four upstanding sides of the block, and provide clamping bolts which are arranged to extend horizontally through the block. The bars keep the sections pressed against each other, and the bolts keep the smaller pieces pressed against each other. Furthermore, the bolts extend through two of the bars and act through the latter to keep the joints tight.

Some provision must be made for movement of the clamping boltis toward and from each other caused by shrinking and swelling of the wood, and, instead of providing each bolt-receiving bar with a series of relatively short bolt-receiving slots, and determining the locations of the bolt-receiving holes in the block by the locations of such slots, as has been the practice hitherto, I make the bolt-receiving holes in the block at, and coincident with, the joints of the block-sections, and make only one bolt-receiving slot in each bar, but each such slot is long enough to take in all the bolts of the block Wherever they may be located. One advantage of the new construction and arrangement is that the block cannot be split by the shrinking action of the wood, because the bolts will always be Specification of Letters Patent.

Patented June 12, 191*? Serial No. 113,011.

capable of lateral slipping movement commensurate with the aggregate degree of shrinkage. With the former construction,

many blocks are split at or between the joints, in consequence of wood shrinkage. For example, if the wood be swelled when the block is made, and if the lateral movement of the bolts be arrested by the slotted bars when the wood shrinks, the glued joints or the wood itself must break apart. By making the holes at'the joints instead of between them, such holes may be made straight by planing grooves in the sections before the latter are assembled, and closefitting bolts of any cross-sectional shape may be used; but, when the holes are made between the joints, as hitherto, they must be bored and their diameter must be substantially greater than that of the bolts which are to be used, because it is nearly always impossible to bore a straight hole through a die block approximately twelve inches wide. A hard wood, such as maple, is generally used for die blocks, but in any event the density or solidity of the wood is so uneven that the boring bit is deflected from its intended straight course. Thus, if a hole is bored as hitherto, its diameter must be enough greater than that of the bolt to allow for deflection of the boring bit, for otherwise the bolt would not go through the hole.

As my bolt-receiving bars do not require any predetermined spacing of the bolts, I may bore the holes for the'latter at the joints of the sections, according to a new method disclosed in my other application, Serial No. 113,010, filed August 3, 1916. The said new method insures straightness, and permits close fitting bolts to be used. If the bolts fit closely, they preclude breaking and separating of the adjacent wood fibers, and keep the top faces of the sections in flush relation.

Of the accompanying drawings Figure 1 represents a top plan view of a die block embodying the present invention.

Fig. 2 represents a side elevation thereof.

Fig. 3 represents a vertical cross section in the plane indicated by line 3-3 of Fig. 2.

Fig. 4 represents a vertical section in the plane indicated by line ll of Fig. 1.

Fig. 5 represents a perspective view ineluding one complete section and a portion of an adjacent section both formed with rectangular bolt-receiving grooves.

Fig. 6 represents a view similar to Fig. 5 excepting that the bolt-receiving grooves are circular.

Fig. 7 represents a sectional view, on a larger scale and in a vertical plane, including contiguous portions of abutting sections provided with a square clamping bolt according to Fig. 4.

Fig. 8 represents a sectional view similar to Fig. 7 excepting that the clamping bolt is circular in cross section and the bolt-receiving hole in the block is circular to conform to the bolt. See Fig. (3.

Figs. 9' and 10 are sectional views similar to Figs. 7 and 8 respectively, excepting that wooden dowels are added.

The same reference characters indicate the same parts wherever they occur.

The block comprises a series of sections abutting each other, and each section com prises a plurality of rectangular pieces a, the latter abutting each other. The sections are indicated at Z). The sections are made separately by gluing the pieces or together, the glued joints thereof being indicated at c. The bolt-receiving holes may be made square or round in cross-section by planing cooperative QI'OOVQS in the meeting faces of the sections before the latter are assembled, or round holes may be bored according to my aforesaid new method of boring, after the sections are assembled. In either case, each hole would comprise two grooves in two contiguous sections respectively. Rectangular grooves (Z are shown in Figs. 4, 5, 7 and 9, and semi-circular grooves (Z are shown in Figs. 6, 8 and 10. The contiguous faces of the sections are glued to make the joints a tight.

If the bolt-receiving holes are rectangular in, cross section, a rectangular bolt 12 will be arranged in each hole; but, if the holes are round, a round bolt 12 (Figs. 8 and 10) will be arranged in each hole. In any case, the bolt-receiving holes will be made to conform to the shape of the bolts, and will be made so that the bolts will substantially fill them, to avoid clearance. The length of the bolts is greater than the width of the block in order that the ends of the bolts may project a substantial distance beyond the block. Screw-tlireads are cut on the ends of the bolts to receive clamping nuts 13.

The block is reinforced by clamping bars, two of which are indicated at 1%, ll, and two of which are indicated at 15, 15. The bars 14 extend parallel to the series of sections and they lie against the upstanding sides of the block. Each bar 1% has an elongated slot 16 that is more than long enough to take in all the clamping bolts. The slots 16 are wide enough to receive the ends of the clamping bolts without leaving clearance from top to bottom. Clamping plates or washers 17 are slipped upon the ends of the clamping bolts outside the bars 14 be fore the nuts 13 are screwed on. When the nuts 13 are set up tightly they force the bars 14 toward each other and thus keep the pieces a pressed firmly against each other to prevent the joints 0 from being opened under the cutting stress when the block is in use.

The bars 1a have screw-threaded shanks 18 at their ends, and the bars 15 are formed with holes so that the latter bars may be slipped upon said shanks. Nuts 19 are screwed upon the shanks- 18 to clamp the bars 15 against the block. thus to keep the sections bpressed againsteach other to prevent the joints 6 from opening under the P cutting stress when the block is in use. If the block shrinks after it is first assembled the shrinkage will be in the di *eetion of the length of the bars let and alsoin the direction of the length of the bars 15; and there will be no shrinkage fromtop tobottom, because the grain of all: the pieces extends from top to bottom. The clamping bars may be set upfrom time to time: to compensate for shrinkage, by tightening. the nuts 13 and 1-9: The pieces and sections 5- may thus always be kept pressed against each other.

It is customary, after the top surface of a block has become concavedl by wear, to

invert the block and. use the opposite sur face. hen this-is done, the block appears as shown by Fig. 2', the bottom surface: in this figure being eoncaved as if by wear. It will be observed that the middle sections do not touch the supporting surface of the bed indicated conventionally by the broken line 20. Consequently, when the pressure head of the die press forces the cutting die downwardly upon a section that does not i touch thebed, suclr section depends for its support upon the adjacent sections and also uponthe bars 14. The cutting stress is transmitted from one section to another by the close-fitting clamping bolts 12* or 1 2" as the case may be, and is transmitted to the bars 14 by said bolts. Inasmuch as the bolts fit accu 'ately in the holes provided for them, they will maintain the top surfaces of the sections in flush relation without dependence upon the glue at the joints for such purpose. The downward stress of the clamping bolts upon the bars- 14 would ordinarily be sustained only by the lower sections of the bars, but the upper sections of the bars may also be utilized to sustain such stress by bending over the top and bottom edges of the plates 17 toprovide lips or flanges 21 (see Fig 3). These flanges fit closely against the top and bottom surfaces (iii of the bars, and the bars therefore are not appreciably weakened by the slots 16, be cause the flanges 21 keep the upper and lower portions of the bars from spreading.

The bars 14 would in practice be from two to five feet long, and it would be difiicult, if not impossible, to form each slot 16 by a single stroke of a die press. Therefore I make each bar 1 1 of two pieces, and weld said pieces in a longitudinal median plane indicated by line mw in Fig. 2.

The fact that the slots 16 include within their range all the joints 0 enables the bars 1 1 to take the clamping bolts wherever the joints 6 may come, and the clamping bolts may move toward and from each other in accordance with the shrinking or swelling of the block.

Although the clamping bolts 12 or 12 fit closely in the holes formed in the block and thus dispense with the necessity of wooden dowels for light work, such dowels may be desirable in conjunction with the bolts if the block is to be subjected to great cutting stresses. For example, Figs. 9 and 10 show dowels 22 extending parallel to the bolts and fitted in registering grooves in the two contiguous faces of the adjoining sections. These dowels help to sustain the stresses from top to bottom, and help to keep the top surfaces of the sections in flush relation so that the sections are not dependent entirely upon the clamping bolts and glue for that purpose.

I claim:

1. In combination, a built-up die block comprising a series of built-up sections abutting against each other, the abutting faces of said sections having registering grooves extending transversely of the block, each pair of such grooves forming a bolt-receiving hole, bolts arranged in said holes and fitting closely against the top and bottom surfaces of the latter, and means coacting with said bolts to clamp the sections transversely.

2. In combination, a built-up die block comprising a series of built-up sections abutting against each other, the abutting faces of said sections having registering grooves extending transversely of the block, each pair of such grooves forming a boltreceiving hole having flat top and bottom surfaces, bolts arranged in said holes, said bolts having fiat top and bottom surfaces fitting closely against said surfaces of said holes, and means coacting with said bolts to clamp said sections transversely.

3. In combination, a builtup die block comprising a series of built-up sections abuting against each other, the abutting faces of said sections extending from top to bottom, said faces having transverse grooves each of which registers with one in the next section to form a bolt-receiving hole, a pair of bars extending parallel to said series and lying respectively against the upstanding sides of the block, means arranged to coact with said bars and to bear against the ends of the block to keep said sections pressed against each other, each said bar having a single slot registering with a plurality of said bolt-receiving holes, bolts extending through said holes and slots, said bolts and holes fitting closely, and nuts coacting with said bolts and bearing against said bars to cause the latter to clamp said sections.

fl:- In combination, a built-up die block comprising a series of built-up sections abutting against each other, the abutting faces of said sections extending from top to bottom, said block having a plurality of transverse bolt-receiving holes traversing the joints between said sections, a pair of bars extending parallel to said series and lying against the upstanding sides of said block, means arranged to coact with said bars and to bear against the ends of said block to keep said sections pressed against each other, each said bar having a single slot registering with said bolt-receiving holes, bolts extending through said holes and slots, said bolts and holes fitting closely, and nuts coacting with said bolts and bearing against said bars to cause the latter to clamp said sections.

5. In combination, a built-up die block comprising a series of built-up sections abutting against each other, the abutting faces of said sections having rectangular grooves extending transversely, each such groove registering with one in the next section to form a rectangular bolt-receiving hole traversing the joint between the sections, a rectangular bolt arranged in and conforming to each such hole, a pair of bars arranged parallel to said series and lying against the upstanding sides of the block, means arranged to coact with said bars and to bear against the ends of the block to keep said sections pressed against each other, each said bar having a single slot registering with said holes, the ends of said bolts extending through said slots, and nuts coacting with said bolts and arranged to keep said bars pressed against said upstanding sides.

6. In combination, a built-up die block comprising a series of built-up sections abutting against each other, the abutting faces of said sections having registering grooves extending transversely and forming bolt-receiving holes, bolts arranged in said holes and fitting closely against the top and bottom surfaces of the latter, the ends of said bolts extending beyond the block, a pair of bars arranged against the opposite sides of the block from which said bolts project,

each said bar having an elongated slot and said bolts extending through such slot, means coacting with said bolts to cause said bars to clamp the block transversely, and means coacting with said bars to clamp the block endwise.

7. In combination, a built-up die block comprising a series of built-up sections and having a series of bolt-receiving holes extending transversely thereof, a pair of bars arranged respectively against the longitudimeans coacting with said bolts to cause said bars to clamp the block transversely, and means coacting with said bars to clamp the block endwise.

In testimony whereof I have aifixed my 20 signature.

ILT-JAM R. FO RSYTH.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of- Patents, Washi-ngton,-D. G. 

